Russian Empire. Miniature (tail-coat) badge of the S-St. Petersburg, Warsaw or Kiev Alexander II of polytechnical institutes. The workshop "DO" - Dmitry Osipov. An assay brand 56, a head in a circle. Type-setting. Extremely seldom meets in gold!!!!
Gold, hot enamel (small chips), type-setting. The 56th test (a shovel, after 1907). Mark "DO", a female head in a circle. Silver nut. The size is 28*22 mm, weight without nut of 6,5 g.